General Rotary Tech Support Use this forum for tech questions not specific to a certain model year
Sponsored by:
Sponsored by: CARiD

?WHAT COUNTERWEIGHT + engone build?

Thread Tools
 
Search this Thread
 
Old Nov 11, 2008 | 12:33 AM
  #1  
R.E.wing_FC3s's Avatar
Thread Starter
*reallly knowing the fc
Tenured Member 10 Years
 
Joined: May 2007
Posts: 160
Likes: 0
From: victory lane
WA ?WHAT COUNTERWEIGHT + engone build?

I need to know the comparative weights of the fd manual front counterweight versus the series 5 turbo manual front counterweight. Or a way to tell them apart.

Im repairing a seized engine and need to replace the eccentric shaft. The front main bearing was fused to the shaft while the rest of the insides still look new? This motor is comprised of fd rotors, fd rotor housings, kouki fc middle and side housings. a kouki fc turbo front cover and flywheel. I believe it had an kouki fc e-shaft, before it was lost.

I was told by mazdaspeed that i could use the e-shaft and main bearings from the rx-8. Does anyone know if this is compatible with the rest of the parts in the motor. like the stationary gears? housings? are the front thrust bearings the same?

Also in order to replace the losr bearing I need a way to calculate the front main bearing clearance. The old front main bearing is fused to the shaft so i cant use it to measure the difference in diameter of the e-shaft o.d. and bearing i.d. Should i just buy a bearing, press it into the gear, and determine the clearance from there? I would hate to waste money on something that won't likely be the right size, any other ideas?
Reply
Old Nov 13, 2008 | 07:12 AM
  #2  
bumpstart's Avatar
talking head
Tenured Member 05 Years
 
Joined: Apr 2008
Posts: 2,775
Likes: 15
From: Perth, WA, OZ
Originally Posted by R.E.wing_FC3s
I need to know the comparative weights of the fd manual front counterweight versus the series 5 turbo manual front counterweight. Or a way to tell them apart.

Im repairing a seized engine and need to replace the eccentric shaft. The front main bearing was fused to the shaft while the rest of the insides still look new? This motor is comprised of fd rotors, fd rotor housings, kouki fc middle and side housings. a kouki fc turbo front cover and flywheel. I believe it had an kouki fc e-shaft, before it was lost.

I was told by mazdaspeed that i could use the e-shaft and main bearings from the rx-8. Does anyone know if this is compatible with the rest of the parts in the motor. like the stationary gears? housings? are the front thrust bearings the same?

Also in order to replace the losr bearing I need a way to calculate the front main bearing clearance. The old front main bearing is fused to the shaft so i cant use it to measure the difference in diameter of the e-shaft o.d. and bearing i.d. Should i just buy a bearing, press it into the gear, and determine the clearance from there? I would hate to waste money on something that won't likely be the right size, any other ideas?
i believe you may want to look at mazdatrix.com for notes on the rx8 shaft
( journals are -.005 inch under the rest )

also that the FD front weight is different manual and auto
the auto ones having the normal sized front torringtons as seen in FC and previous RX
and manual ones having larger race for larger torringtons suit FD pull clutch

i would suggest your original weights were likely kouki all around
( if light fly and weight )
as these paired together also suit the kouki and FD rotor weights

its ok to proceed carefully !!!
Reply
Old Nov 17, 2008 | 02:55 PM
  #3  
diabolical1's Avatar
Moderator
Tenured Member: 20 Years
Liked
Loved
Community Favorite
iTrader: (3)
 
Joined: Feb 2002
Posts: 10,998
Likes: 349
From: FL
if you're trying to match counterweights as opposed to just balancing a rotating assembly with what you have, then match them to the rotors you're using. period. the shaft shouldn't matter as much.

that said, both the REW and Renesis shafts are tapered, but there is question whether or not they share the same hardening process. clearances should not be too big an issue, as Mazdatrix told me i could use the 8's main bearings in my REW if i so chose.
Reply




All times are GMT -5. The time now is 10:18 AM.